This invention generally relates to navigation or route guidance systems and, more particularly, to a navigation system that provides a predefined non-voice audio maneuver instruction to notify the navigation system user of an upcoming maneuver.
Navigation systems generally provide a recommended route from a starting point to a desired destination. Generally, the starting point and desired destination are selected from a large database of roads stored in a mass media storage, such as a CD ROM, which includes the roads in the area to be traveled by the user. If the navigation system is installed in a vehicle, the starting point is typically the current position of the vehicle, which can be input to the navigation system by an associated position determining system that usually includes a GPS (Global Positioning System) receiver.
The navigation system determines a route from the starting point to the destination utilizing an algorithm well-known to those in the art and currently in use in many navigation systems. Usually there are many potential routes between the selected starting point and the desired destination. Typical navigation systems select a recommended route based upon certain xe2x80x9ccostxe2x80x9d values associated with each segment of road in the road database. These cost values include the length of the road segment and the estimated time of travel through the road segment. The navigation system selects the potential route with the lowest total cost to be the recommended route. Depending upon the predetermined algorithm of the navigation system, the navigation system will recommend the route with the shortest total length, the lowest total time, or some weighted average of length and time.
The recommended route is then displayed to the user as a map showing the starting point and desired destination and highlighting the recommended route. Preferably, if the navigation system is installed in a vehicle, the navigation system displays the current position of the vehicle and provides visual turn-by-turn instructions to the driver, guiding the driver to the selected destination.
Many navigation systems also provide audible turn-by-turn instructions to the diver. To give the driver time to refer to the system display, the turn-by-turn instruction is typically provided a fraction of a mile away from the actual desired maneuver. The driver may therefore have trouble identifying a particular maneuver with the surroundings. This is particularly troubling in a highly congested and road intense environment such as a city. Another disadvantage of such a system is that drivers do not always correlate a single tone or voice command with an upcoming maneuver. The drivers must therefore look at the navigation system to assure themselves of what maneuver they are to perform. This necessarily decreases the intuitive value of the navigation system and thus decreases the benefit of providing audio information.
It is thus desirable to provide a system for projecting definite non-voice audio maneuver instructions that enhances the ability of a driver to correctly perceive the content of the instruction without refelting to a visual display.
In general terms, this invention provides a vehicle navigation system in combination with a vehicle audio system that provides non-voice audible maneuver instructions to a driver immediately prior to an upcoming maneuver.
The navigation system generally includes a database of a plurality of roads, a position determining system, an input device, and a route determination system. The position determining system determines a position of the vehicle relative to the plurality of roads. The user selects a destination from the database with the input device. The navigation system then calculates and displays a recommended route directing the driver of the vehicle to the desired destination. Preferably, the navigation system displays turn-by-turn instructions on a display and gives corresponding audible instructions on an audio speaker to guide the driver to the desired destination.
As the vehicle approaches an upcoming maneuver the display switches from a large-scale map display screen to a maneuver instruction screen. The maneuver instruction indicates to the driver the next maneuver to be performed along the recommended route to the destination, such as a turn arrow. The maneuver instruction screen also displays a countdown display such as a bar graph which indicates the imminence of the upcoming maneuver. The user is thereby provided with constant information on the upcoming maneuver and the distance to the upcoming maneuver. This is particularly advantageous in a highly congested or road intense environment such as a city.
When the vehicle is very near the execution of the upcoming maneuver, it is preferable to provide a non-voice audible maneuver instruction that is always consistent with the upcoming maneuver. For example only: a right turn can be a low tone followed by a high tone; a left turn can be a high tone followed by a low tone; a straight ahead instruction can be a mid-level tone followed by another mid-level tone; and a U-turn can be a a high tone followed by a low tone followed by a high tone. After a short familiarization period the driver will intuitively identify a particular tone or series of tones with a particular maneuver. Further, by only providing the non-voice audio maneuver instruction within a relatively short distance prior to the upcoming maneuver, such as within one-tenth of one mile, the driver will identify the tone(s) with the immediacy of the upcoming maneuver as opposed to a repetitive and less urgent voice instruction.
In another embodiment of the present invention, the non-voice audible maneuver instruction can also be provided as a three-dimensional (3D) environment. The navigation system is connected to the vehicle sound system and a plurality of speakers. The navigation system CPU would initially begin projecting the instruction through a loudspeaker, which is in a location that does not coincide with the direction associated with the instruction. While projecting the instruction the CPU would also begin projecting the instruction through another loudspeaker that does correspond with the maneuver. The CPU would then complete projecting the first non-voice maneuver instruction entirely from the second loudspeaker. This movement of the instruction will create a xe2x80x9cwhooshingxe2x80x9d effect that will enhance the ability of the driver to perceive the content of the first non-voice audible maneuver instruction.
These and other features and advantages of this invention will become more apparent to those skilled in the art from the following detailed description of the presently preferred embodiment. The drawings that accompany the detailed description can be described as follows.